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What Is It? |
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Both
rules have patent numbers stamped on the body that are of British
origin. However, the British patent office system is somewhat
confusing—the number can refer to an application, the intent
to apply, a design or registered design or the granted patent.
It is also interesting to note that there was no prescribed
method for detailing a patent in the English system, so descriptions,
applications and final tool markings are extremely varied, making
a coherent search difficult. The Hainsworth patent (no. 2523)
dates from 1852-1855 and the Harrison patent (no. 24458) shows
a date from 1892-1893. |
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The
production of wooden drawing aids was slowly eliminated by the
1920s due to the emergence of plastics and other man-made materials.
Today's use of Computer-Aided Design (CAD) is supplanting the
hand-drawn plan and simple architectural concept drawings with
the use of a mouse, central processing unit and a computer screen.
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D.S.
Orr |
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Other Articles from this Issue |
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